First-order coherence of light emission from inhomogeneously broadened mesoscopic ensembles

TL;DR

This paper demonstrates that the first-order coherence of light emitted from mesoscopic ensembles with inhomogeneous broadening can be analyzed to estimate individual emitter properties, using a simple model and numerical methods.

Contribution

It introduces a method to extract emitter linewidths and numbers from ensemble autocorrelation functions despite inhomogeneous broadening.

Findings

Emitter linewidths can be estimated from autocorrelation functions.

The method applies to mesoscopic systems with 10 to 10^4 emitters.

Analysis of colloidal nanocrystal photoluminescence validates the approach.

Abstract

Inhomogeneous broadening is well known to hinder individual characteristics of emitters, supplanting the single-particle properties by their broader probability distribution. Here, we present an analysis of the emission spectra of mesoscopic ensembles of inhomogeneously distributed emitters below the thermodynamic limit (10 - 10^4 emitters). Based on a simple analytical model and an extensive numerical analysis, we show that the number and individual linewidths of the emitters can be directly estimated from the ensemble autocorrelation function in spite of an inhomogeneously broadened emission. As an application, we analyze the photoluminescence of colloidal nanocrystal aggregates embedded in a gold shell. Our general method can be applied to a wide range of mesoscopic many-body systems and could provide new insights into their first-order coherence properties.